Comparison of efficacy of propofol given by closed-loop infusion for surgery in pediatric patients of different ages

Objective To compare the efficacy of closed-loop infusion of propofol for surgery in pediatric patients of different ages. Methods Forty-five pediatric patients of both sexes, weighing 10-63 kg, of American Society of Anesthesiologists physical statusⅠ or Ⅱ, scheduled for elective urologic surgery under general anesthesia, were divided into 3 groups (n=15 each) according to the age: infant group (1-3 yr), pre-school group (4-6 yr) and school-age group (7-12 yr). The bispectral index (BIS) monitor was connected to the closed-loop anesthesia delivery system, and the system automatically regulated the target plasma concentration of propofol to achieve a target BIS value of 45-55 during maintenance of anesthesia.Remifentanil was given by target-controlled infusion at a target plasma concentration and rocuronium was intravenously injected when necessary during surgery.BIS40-60 time percentage (percentage of time of BIS value maintaining at 40-60 in time of closed-loop infusion), median performance error (MDPE), median absolute performance error (MDAPE), wobble and global score were recorded.The consumption of propofol, mean target plasma concentration and regulating frequency and consumption of remifentanil and rocuronium were recorded during surgery.Extubation time or laryngeal mask airway removal time, time to eye-opening and time of regaining consciousness were recorded. Results The BIS40-60 time percentage was significantly higher, MDPE, MDAPE, wobble and global score were lower in pre-school and school-age groups than in infant group (P 0.05). There was no significant difference in the consumption of propofol, mean target plasma concentration, regulating frequency, consumption of rocuronium, extubation time or laryngeal mask airway removal time, time to eye-opening or time of regaining consciousness among the 3 groups (P>0.05). Conclusion Closed-loop infusion of propofol produces better stability for surgery in pre-school and school-age children than in infants. Key words: Propofol; Drug dilivery systems; Child